Injuries have taken a toll on the Chargers' outside linebackers this year.

On Thursday, the unit had a positive health development.

Jarret Johnson returned to practice, one week after aggravating a hamstring injury. The starting strong side, or "Sam," linebacker has missed three of the past four games with the ailment, including Sunday's against the Broncos.

Chargers at Dolphins, 11/17/13

The Chargers spent most of that afternoon without their top four outside linebackers.

Melvin Ingram tore an anterior cruciate ligament in May. Dwight Freeney tore a quadriceps tendon in September. With Johnson inactive, Larry English tore a pectoral muscle in the second quarter when sacking quarterback Peyton Manning.

“I can't control injuries," coach Mike McCoy said. "You have no control; that's all part of the game. No one is going to feel sorry for us on Sunday. ... If I had the answer for why they were happening, hopefully I would have prevented them. Every team is dealing with it throughout the year. We've had our fair share of them."

English joined Freeney this week on season-ending injured reserve.

Ingram, on the Physically Unable to Perform list, is tentatively expected to practice next week, but the team plans to evaluate him again before finalizing any decision, a source said Thursday. It remains to be seen whether the 2012 first-round draft pick will play this year.

Thomas Keiser began the season on the practice squad but played all 61 defensive snaps Sunday in his first career NFL start. Tourek Williams, a rookie sixth-round choice, took 46 defensive reps, matching his career total entering the game.

Johnson first injured his hamstring Oct. 6 in the fourth quarter against the Raiders. He was limited in Thursday's practice. His availability to face the Dolphins will be listed Friday as part of the team's final injury report.

“Anytime you can get a veteran player back is great,” defensive coordinator John Pagano said. “It's just sad because you really saw Larry turning that corner and his progress each game. The biggest blow for us is losing a guy that plays with unbelievable effort and gives it his all on the field no matter what rep he is doing.

“I think the injury came when he got a sack, so it's frustrating for him, but any chance you have of getting a guy back, and hopefully we do get Jarret back, is definitely going to help us."